SU1601330A1 - Method of setting a patch in unsealed interval of casing - Google Patents

Abstract

The invention relates to the oil industry and is intended for the repair of casing strings and the isolation of flooded productive formations in the perforation zone. The goal is to save material plaster. On the pipes they lower hydraulic packers with sealing elements and a plaster mounted on them. Then, the upper end of the lower sealing element of the hydraulic packer is placed opposite the lower limit of the leakage interval. The length of the patch is calculated using a mathematical formula. The packer sealing elements are packed in the end sections of the patch and the patch is expanded along the entire length by creating an overpressure in the packing elements of the packers and in the interpacker zone. Such an arrangement ensures the safety of the plaster and its casing in the interval weakened by the holes. 4 il.

Description

f

(21) 4446602 / 23-03

(22) 04/25/88

(46) 10/23/90. Bul No. 39

(71) All-Union Scientific Research Institute of Drilling Technology

(72) A.A.1b1bin, V.V.Toropynin, A.N.Gladkikh, S.P.Tarasov

and A.V. Pranevsky

(53) 622: 245.4 (088.8)

(56) USSR Author's Certificate No. 1035192, 101. E 21 B 33/10, 1981.

USSR Author's Certificate No. 1141184, cl. E 21 B 29/10, 1983.

(54) METHOD OF INSTALLATION OF W 1 ASHEARS IN THE INTERVAL OF NON-TIGHTNESS. SECONDARY COLUMN

(57) The invention relates to the oil industry and is intended for the repair of casing strings and the isolation of flooded productive layers of perforated flowerpot. The goal is to save material plaster. Hydraulic packers with sealing elements and a plaster mounted on them are released on the pipes. Then, the upper end of the bottom plate of the hydraulic packer is placed opposite the bottom of the leakage interval. The length of the patch is calculated by the mathematical term. The packer sealing elements are packed in the end sections of the patch and the patch is expanded along the entire length by creating an overpressure: NIN in the packing elements of the packers and in the interpacker zone. Such an arrangement of the patch ensures the preservation of its casing string in the interval weakened by the holes. 4 il.

with s

L

The invention relates to the oil industry, in particular to methods for repairing casing strings, as well as to isolating the watering of productive formations in the perforation zone.

The aim of the invention is to provide economy of material of the patch.

On (JMF. 1 shows a dual hydraulic packer (ORS) with a plaster installed on it in the transport position; Fig. 2 - the same when packing its sealing elements on the plaster; Fig. 3 - the same, when pressing the end sections of the plaster Fig. 4 - the same, when the end sections are pressed and the middle section is deformed before touching the inner surface of the casing. The method of installing the patch in the casing leakage interval is implemented as follows.

A hydraulic patch 4 is placed on the hydraulic packer, which includes the upper 1 and lower 2 sealing elements, between which the daFantal valve 3 is placed, which is fixed on the packer by means of the fasteners 5 and 6. The distance between the sealing elements and 2 is established depending on from the length of the patch, defined by dependency, and secured

with

nor complete closure of the sealing elements 1 and 2 of the end-ends with segments

 The length of the patch is chosen in accordance with the following dependence.

(1 where).

1 "H - 1E With ts

20

25

f

thirty

F E- (length of plaster, m; length of casing leakage interval, m; length of the sealing element of the hydraulic packer, m ;. P--. Pressure in hydraulic pairs- ° cara when the end sections of the plaster are pressed, MPa; distance from wellhead to the upper limit of the casing leakage interval, m;

Yudul elasticity of the material of the pipe on which the release is done, MPa; the ratio of the outer diameter to the inner tubes on which the plaster is released;

Poisson's ratio of the material of the pipe on which the plaster is released. A packer with plaster 4 is run down on Tubing (unplugged) In the casing 7 to the inter-ID leaking leakage weakened by the Holes 8, the Lower sealing Element 2 is set so that the upper end face is opposite the lower limit of the interval 1 In this case, the distance between the lower end of the upper sealing element 1 and the upper limit of the interval (will amount to a, equal to 2 taking into account

   /

lengthening of tubing pipes Ori Ori plaster. An overpressure of about 2-3 MPa is created in the packer and sealing elements 1 and 2 are wrapped in the red areas of the patch 4 (FIG. 2). I increase the pressure in the pack and first expand it with sealing elements 1 and 2 corresponding end sections of the plaster (4g, 3), after which the differential valve 3 is opened, which is preset to; the set pressure, 55 And the working fluid expands the average part of the patch. The pressure in the packer is increased to the calculated P, which ensures the pressing of the end sections of the plate35

40

s

0

five

0

0 5

five

0

At the same time, the middle part of the patch in the interval 1 is deformed by the calculated pressure to touch the inner surface of the casing to eliminate loads on the interval l.g (Fig. 4). In the process of installation, patch 4 together with the packer is moved relative to the casing Ig interval by the value a / 2, but due to the selection of the length of the patch and its corresponding orientation before installation relative to the lower boundary of interval 1, the end sections of the patch pressed to the casing will be outside the interval Ij, at an equal distance a / 2 from their respective boundaries. Such an arrangement of the plaster will ensure its safety and the casing string in the interval weakened by the holes.

Claims (1)

The method of installation of the patch in the interval of casing leakage, including the descent on the pipes of hydraulic packers with sealing elements and installed on i-plx plastics, packing of sealing elements of the packer in the end sections of the patch and expanding the adhesive along the entire length by creating an excess pressure in the sealing elements of the packers and in the inter-packer zone, which is due to the fact that j, in order to save material, the plaster, after descending the plaster, the upper end of the lower seal itelnogo element. hydraulic packer is placed opposite the lower limit of the interval of leakage, and the length of the patch is chosen in accordance with the following relationship L.i, .2ci:;,. 5 - ixu)); , E- (C -l). where L is the length of the plate, m; Ij is the length of the casing leakage interval, m; 1 (,,. 3 - length of the sealing element of the hydraulic packer, m; P - pressure in the hydraulic packs when pressing the end, sections of the patch, MPa; 1 - distance from the wellhead to the upper boundary of the casing leakage interval, m; E - the modulus of elasticity of the material 1601330 tubes that release plaster, MPa; the ratio of the outer diameter to the inner tubes on which 1 a patch is being released; | V (- Poisson's ratio of the material of the pipes on which the plaster is released. 2 7Fig. Compiled by I.Levkoeva Editor V. BugrenkovaTehred L.SerdyukovaKorrector I.Musk Order 3257 Circulation 469 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, 4/5 Raushsk Nab. Subscription